As Gracie Abrams roamed the Greek Theatre stage Monday, the pit dwellers’ outstretched arms resembled flames licking the hem of her sheer black maxi skirt. But despite the night’s sweltering heat, she crouched down to touch the fire.

Rising, she clutched her heart, as though storing the warmth there.

The first of three hometown shows on Abrams’ Secret of Us tour, Monday’s sold-out affair saw many such intimate moments between the 25-year-old singer-songwriter and her doting fans. It’s a pattern of Abrams’ that hasn’t changed from her earliest live shows to her opening sets last summer on Taylor Swift’s Eras tour — she blows kisses, holds hands and whispers “I love you” under her breath, all with the sincerity of a close friend.

“This is real to me,” Abrams told those at the show Monday. “Like, this relationship means so much, and I really mean it when I say I attempt to weave your generosity into my songs and stories.”

Whereas other artists might write off highly personal emails and unsolicited self-disclosure from their fans as inappropriate or plain annoying, for Abrams, it’s a reminder “that we’re really all going through the same s— at the end of the day.” It keeps her honest, and it keeps her writing.

Hence, even though she didn’t plan to put out new music so soon after releasing her debut album, “Good Riddance,” in 2023, she had another album on her hands before she knew it.

Released June 21, “The Secret of Us” debuted at No. 2 on the Billboard 200 — trailing Taylor Swift’s “The Tortured Poets Department” — with 89,000 album-equivalent units, becoming Abrams’ first top 10 and highest-charting album.

When presales went live in June for the Secret of Us tour, the originally scheduled solo L.A. date, Sept. 11, sold out within an hour, so Abrams booked a second slot on Sept. 12 — and later, a third that became L.A.’s opening night. Olivia Rodrigo, “Twisters” star Daisy Edgar-Jones and “Bridgerton” alum Phoebe Dynevor were among the attendees.

Gracie Abrams performs.

(Lauren Tepfer)

Clocking in at just under two hours, the show began with album opener “Felt Good About You,” a folksy number whose jaunty tambourine gives it the feel of a tune from an indie film soundtrack. Even though Abrams performed the song behind a semi-transparent partition, her stage presence was palpable as her silhouette swayed with the rhythm.

Moving to center stage, Abrams threw on an acoustic guitar with a star-patterned strap for “Risk,” the lead single from “The Secret of Us.” She was delighted as fans shouted lyrics back to her, and even during the scathing “Blowing Smoke,” she couldn’t stifle her smiles.

Later, she yielded completely to dueting with audience members, offering them her mic for lyrical punchlines from “21,” “I Love You, I’m Sorry” and “Mess It Up.” All the while, she flexed her vocal control, much-improved since her last headlining tour. Swapping out the shorter, lower notes from such poignant tracks as “Where Do We Go Now?” and “Gave You I, Gave You I” for longer, higher ones, she drew gasps from even the least expressive concertgoers. (A security guard was filming at one point.)

For Monday’s “surprise song,” a relic from her time studying under Swift, Abrams brought onstage her best friend, roommate and “The Secret of Us” co-writer Audrey Hobert. After some mutual gushing, the two did a duet of the unreleased “That’s So True,” exchanging dramatized expressions as they sang, “Smiling through it all, yeah that’s my life.” Combining juvenile lyrics with adult themes, the song manifests Abrams’ simultaneous preoccupation with teenage girlhood and position beyond it — something else she shares with Swift.

After a stripped down “Good Luck Charlie” came a series of songs whose live production elements, on top of exemplifying Abrams’ growing sense of playfulness as a performer, vastly improved upon their studio versions. “Friend,” a soft pop B-side from Abrams’ debut EP “minor,” for one, benefited from added distorted synth. And “Normal Thing,” a grower from Abrams’ latest album, was transformed with a heart-rending drum build.

Conversely, the live versions of “Feels Like” and “Free Now” — the set closer — left their admirers wanting, with the former’s speeded-up rendition especially being critiqued online. Still, any discontentment was quickly assuaged by a knockout encore.

After taking the stage again to deliver a dynamic performance of “Us,” complete with Swift’s vocals on a backing track, Abrams officially closed L.A. Night 1 with the song fans begged her for seven years to release.

Fans sporting hair ribbons watch Gracie Abrams’ concert at the Greek Theatre on Monday.

(Lauren Tepfer)

“Close to You,” a synth-pop “earworm” — as Abrams calls it — about feverishly yearning for someone, was her best-performing single upon release, getting more than 3 million streams in its first day on Spotify and going on to hit No. 49 on the U.S. Billboard Hot 100 — her first solo entry on the chart.

“OK, ready?” Abrams grinned teasingly at the crowd as the track faded in. The moment the pre-chorus hit, half the stadium was in the air.

As the song went on, and teenage girls in hair ribbons and lace skirts were projected onscreen, Abrams’ plea for closeness seemed directed more toward them than an unrequited crush.